Pekin Ducks? I'm not sure hehe I don't have experience with them, but I do know that quail and chickens usually don't mix due to pecking injuries/chickens can carry disease that can kill off quail fast but has no symptoms in the chickens.

Chickens shouldn't be kept with pet/exotic birds. Chickens are carriers of diseases that may not affect them but can be fatal to your pet birds. Chickens should be kept separate and good hygiene observed between your handling of chickens and your pet birds. Diseases can be tracked in on shoes or even just blown there by the wind if their enclosures are close. I have an aviary but it's at the front of our house whereas our chicken coop is way out the back.